Upgrade Hazelcast 4 to 4.2.3

Closes gh-1979

Author: eleftherias

spring-session-hazelcast/hazelcast4/hazelcast4.gradle

@@ -21,7 +21,7 @@ artifacts {
 
 dependencies {
     api project(':spring-session-core')
-    optional "com.hazelcast:hazelcast:4.2.2"
+    optional "com.hazelcast:hazelcast:4.2.3"
     api "org.springframework:spring-context"
     api "javax.annotation:javax.annotation-api"
 
@@ -35,7 +35,7 @@ dependencies {
     testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine"
 
     integrationTestCompile "org.testcontainers:testcontainers"
-    integrationTestCompile "com.hazelcast:hazelcast:4.2"
+    integrationTestCompile "com.hazelcast:hazelcast:4.2.3"
     integrationTestCompile project(":spring-session-hazelcast")
 }
 

spring-session-samples/spring-session-sample-boot-hazelcast4/spring-session-sample-boot-hazelcast4.gradle

@@ -7,7 +7,7 @@ dependencies {
 	implementation  "org.springframework.boot:spring-boot-starter-actuator"
 	implementation  "org.springframework.boot:spring-boot-starter-thymeleaf"
 	implementation  "org.springframework.boot:spring-boot-starter-security"
-	implementation  "com.hazelcast:hazelcast:4.2.2"
+	implementation  "com.hazelcast:hazelcast:4.2.3"
 	implementation "nz.net.ultraq.thymeleaf:thymeleaf-layout-dialect"
 	implementation "org.webjars:bootstrap"
 	implementation "org.webjars:html5shiv"